The following line:
y(t+2) - 2Y(t+1) + 3Y(1) = 4
should be:
y[t+2] - 2y[t+1] + 3y[1] == 4
Parentheses are NOT used for function notation in Mathematica, and "="
causes its left operand to be Set. You also mixed small and capital Y
in that line -- they're two different symbols.
Bobby Treat
-----Original Message-----
From: Andrew Biggs [mailto:agbiggs at hotmail.com]
To: mathgroup at smc.vnet.net
Subject: [mg35141] [mg35127] Difference /recurrence equations
I'm new to Mathematica and am having trouble with inputting the
equations I'm looking to solve. I know the basic input of RSolve, but
can't quite get it. Here's a sample problem, if anyone could show me
how to input into RSolve I can probably run with the ball after that.
y(t+2) - 2Y(t+1) + 3Y(1) = 4
With the part in brackets being a subscript denoting time. I know it
sounds dumb, but I just don't know the input notatin well enough to
get a problem typed in correctly, and the Mathematica book is a little
overwhelming.
Any help greatly appreciated!
Andrew